


Today we discover the therapeutic effect of wonderful smelling herbs, flowers, and fruit. 

This episode features audio from Lavender for Generalized Anxiety Disorder, Orange Aromatherapy for Anxiety, and Peppermint Aromatherapy for Nausea. Visit the video pages for all sources and doctor’s notes related to this podcast.



Here’s a question for you. What’s the best way to live a longer, healthier life? Diet? Exercise? Both—eating healthy while doing jumping jacks? Welcome to the Nutrition Facts Podcast. I’m your host Dr. Michael Greger and I’m here to help you answer that question. We have tremendous power over our health destiny and longevity. The vast majority of premature death and disability is preventable with a healthy enough diet and lifestyle. And, I’m here to bring you the latest peer-reviewed research to give you the tools to put it into practice.

Today, we discover the potential therapeutic effect of wonderful smelling herbs, flowers, and fruit.

In our first study, lavender oil was tested against the valium-like drug lorazepam (sold as Ativan) for relief of persistent anxiety.

Lavender oil, distilled from lavender flowers, is “most often used in aromatherapy and massage. Despite its popularity, only recently have scientifically-based investigations been undertaken into its biological activity,” however. There have been “small-scale studies” suggesting benefit from lavender massage; but, maybe it’s the massage, not the lavender.

There was a study on patients in intensive care, comparing massage with odorless oil to massage with lavender oil, and though patients massaged with lavender oil did say they “felt less anxious and more positive,” there were no objective differences found in terms of blood pressure, breathing, or heart rate. Frankly, maybe the lavender was just covering up the nasty hospital smells.

Subsequent studies using more sensitive tests did find physiological changes, though. We know, for example, the smell of lavender changes brain wave patterns. But, what effect does this have? Well, evidently it makes people feel better, perform math better (faster and more accurately), whereas the smell of rosemary, for example, seemed to enable folks only to do math faster not necessarily with greater accuracy.

What if you actually eat lavender flowers, or, in this case, take capsules of lavender-infused oil, so you could double-blind the study to compare lavender head-to-head to a drug like Valium (lorazepam, known as Ativan), for generalized anxiety disorder.

Generalized and persistent anxiety is a frequent problem, and is treated with benzodiazepines—benzos or downers, like Valium. “Unfortunately, these substances” can not only make you feel like you have a hangover, but “have a high potential for drug abuse” and addiction.

So, they decided to give lavender a try. The drug Ativan certainly reduces anxiety, but, so does lavender. By the end, you couldn’t tell which was which. And, in fact, among those that responded to either, the lavender actually seemed to work better.

“Since lavender oil has no potential for drug abuse and causes no hangover effects it appears to be an effective and well-tolerated alternative to benzodiazepine drugs for the amelioration of generalised anxiety.”

One cautionary note, however; there was a case series published in the New England Journal of Medicine. “Pre-puberty Gynecomastia Linked to Lavender.” Reports of young boys exposed to lavender-containing lotions, soaps, hair gel, and shampoo starting to develop breasts, which disappeared after these products were discontinued suggesting that lavender oil may possess hormone-disrupting activity.

And, indeed, when dripped on estrogen receptor-positive human breast cancer cells, lavender does show estrogenic effects, and a decline in male hormone activity, though it’s unknown if similar reactions occur inside the body when lavender flowers or lavender oil is ingested.

In our next story, the smell of sweet orange essential oil is found to have anxiety-reducing properties without the potentially addictive, sedating, and adverse effects of Valium-type benzodiazepine drugs.

“Aromatherapy is the use of concentrated essential oils extracted from plants to treat diseases,” and is “commonly used” to treat anxiety symptoms. “Anxiety disorders are the most prevalent class of psychiatric disorders in the general population. However, their treatment is still challenging, as the drugs used for the relief of anxiety symptoms can have important side-effects.”

Thankfully, “Double-blind, randomized, placebo-controlled clinical trials performed to evaluate the effects of essential oils on anxiety symptoms are gradually starting to appear in the medical literature. However, in most of these studies, exposure to the essential oil odor was accompanied by massage. This makes it difficult to draw firm conclusions about the effect of the aroma itself.”

Here’s a typical example: patients in the intensive care unit the day after open-heart surgery getting foot massages with orange-scented oil. Why not back massages? Because they just had their chests cracked open, so they have this huge “sternotomy wound.” Maybe a preventive plant-based diet, rather than a post-op plant-based massage, might have been the better choice. But the massages felt great, “restful, peaceful, and calming.” You know it’s a British study because “one described the effect as ‘smashing.’”

But, how do we know the essential oil had anything to do with it? Maybe it was just the massage that was so bloody good; in which case, great, let’s give people massages! I’m all for more ICU foot rubs. “There is considerable evidence from randomized trials that massage alone reduces anxiety.” So, if massage is effective, then aromatherapy plus massage is also effective. So, aromatherapy may work, even if it doesn’t.” In fact, one study, where cancer patients got massaged during chemo and radiation, even found that the massage without the fragrance may be better. They thought it might be like a “negative Pavlovian” response. You know, people smell the citrus, and their body is like “Oh, no; another, you know, cancer treatment!”

More recently, the “ambient odor of orange” was tested in a dentist’s office to see if it “reduces anxiety and improves mood.” “Ambient odor of orange was diffused into the waiting room.” It appeared to have “a relaxant effect”—less anxiety, better mood, and more calmness, compared to a control group where there was no odor in the air. No odor, that is, except the nasty dentist office smell. Maybe the orange scent was just masking the unpleasant odors. Maybe it had nothing to do with any kind of orange-specific molecules. More research was necessary.

“The effect of sweet orange aroma on experimental anxiety in humans.” They exposed some grad students to an anxiety-producing situation, and tested the scent of orange, versus a non-orange aroma, versus no scent at all. And, the orange did appear to have an anxiety-reducing effect. Interestingly, the observed anxiety-reducing effects was not followed by physical or mental sedation. “On the contrary, at the highest dose, the orange oil made the volunteers feel more energetic.” So, potentially less anxiety, without the downer effect of Valium-type drugs.

So, does that mean we can get the benefits without the side effects? Well, I’ve talked about the concerns of using scented consumer products—even ones based on natural fragrances. And, there have been reports of “adverse effects of aromatherapy”—in fact, some pretty serious reactions.

Alternative medicine isn’t necessarily risk-free. Like, there are dozens of reported cases of people having their hearts ruptured by acupuncture. Ouch.

But, the adverse effects of aromatherapy were mostly from “skin irritation” from essential oils being applied topically to the skin or, even worse, swallowed. Certain citrus oils can make our skin sensitive to sunlight. Though, less of a problem in France, evidently, where they’re known to stick them where the sun doesn’t shine.

Finally, we look at the relief peppermint may have for nausea after surgery.

One of the most common fears patients express when facing surgery is postoperative nausea and/or vomiting (PONV), which ranges from minor queasiness to protracted periods of vomiting. Feeling sick to one’s stomach and throwing up after surgery is a common problem, affecting between a quarter and half of those placed under general anesthesia, and more than half of those at high risk. Who’s at high risk;  women who don’t smoke and have a history of motion sickness. I’ve explored the science behind treating nausea with ginger, but if you’re too nauseous to eat, what do you do? Well, people are often sent home with anti-nausea rectal suppositories. However, surveys show that cultural and sexual attitudes may make a number of people sensitive to anything involving the rectum, but the wording of the survey question they asked was, are you happy to have a drug put up your back passage? And I can imagine many of the respondents thinking well, maybe I wouldn’t mind so much, but I wouldn’t exactly be happy about it–especially when you’re feeling sick and throwing up.

And for women after a C-section, they might not want to take drugs–regardless of the orifice–if they’re breastfeeding, so researchers decided to put aromatherapy to the test. Research has shown that essential oils of both spearmint and peppermint are effective in reducing nausea and vomiting after chemotherapy, but this was after taking them internally: swallowing them. Would just the smell of peppermint help with nausea? They had women take deep whiffs of peppermint extract, like you’d buy at a store, and it seemed to work. While none sniffing plain water with green food coloring—the placebo—or the control group who didn’t sniff anything, none of them felt better. 80% of the mint sniffers felt better within just a few minutes.

The study was criticized for being small, and for not using pure peppermint oil. Peppermint extract is peppermint oil plus alcohol—maybe it was just the smell of alcohol that made people better! And that’s actually not much of a stretch. In 1997, researchers reported a simple, innocuous, and inexpensive treatment for postoperative nausea and vomiting—the smell of isopropyl alcohol, which is what’s found in those alcohol wipes, the little prep pads that nurses swab you with before shots. They found out that they could just effectively tear one open and wave it under someone’s nose, and relieve nausea and vomiting in more than 80% of folks after surgery. It’s been since shown to work as well as a leading anti-nausea drug, and may even work faster, cutting nausea in half within 10 to 15 minutes, rather than 20 or 25.

So was it the alcohol, the peppermint, or both? We didn’t know, until it was put to the test. Patients were instructed to take three slow, deep breaths, inhaling through the nose and exhaling through the mouth, smelling alcohol, peppermint, or nothing. The smell of peppermint cut nausea in half within 5 minutes. And so did the alcohol. But so did smelling nothing. So maybe it had nothing to do with the scent; maybe it was just the instruction to take slow, deep breaths. That would make it a really cost-effective intervention, if all we had to do was tell people how to breath. Maybe it shouldn’t be so surprising, given the proximity of the vomiting and breathing centers within the brain.

And indeed, controlled breathing was effective with or without any scent. So next time you feel nauseous, inhale deeply through your nose to the count of three, hold your breath to the count of three, and exhale out the mouth to the count of three. And do that three times. Ironically, the researchers continued to advocate using that nasty smelling alcohol pad even though they showed it wasn’t any more effective than breathing alone. Why would they do that? Because since isopropyl alcohol has a readily detectable odor, patients are more likely to think that their post-operative nausea and vomiting are being actively treated when they inhale alcohol vapors rather than just engaging in breathing exercises.

We would love it if you could share with us your stories about reinventing your health through evidence-based nutrition. Go to NutritionFacts.org/testimonials. We may be able to share it on our social media to help inspire others. To see any graphs charts, graphics, images or studies mentioned here, please go to the Nutrition Facts Podcast landing page. There you’ll find all the detailed information you need plus links to all of the sources we cite for each of these topics.

NutritionFacts.org is a nonprofit, science-based public service, where you can sign up for free daily updates on the latest in nutrition research via bite-sized videos and articles. Everything on the website is free. There’s no ads, no corporate sponsorship. It’s strictly non-commercial. I’m not selling anything. I just put it up as a public service, as a labor of love, as a tribute to my grandmother –whose own life was saved with evidence-based nutrition. Thanks for listening to Nutrition Facts. I’m your host, Dr. Michael Greger.

One response to “Aromatherapy!

Comment Etiquette



The Short List




View the Full Community Guidelines

Leave a Reply


Pin It on Pinterest

Share This